Apparatus for pasteurizing milk for feeding to calves

ABSTRACT

The present invention is directed to a system and method for pasteurizing milk and colostrum for feeding to calves. The system includes a vat for storing milk or colostrum, a circulation pump and piping system, a heat exchanger for adjusting and/or maintaining milk temperature, and an ultraviolet light pasteurizing unit (“UV reactor”) that treats the milk without damaging important immunoglobulins.

FIELD AND BACKGROUND OF THE INVENTION

This invention relates generally to liquid sterilization systems andmore particularly to apparatus and methods for pasteurizing milk andcolostrum for feeding to calves.

Calves in dairy harvesting facilities are fed non-saleable (“waste”)milk collected from cows that have been removed from the main herd formedical or other reasons. While the feeding of non-saleable milk todairy calves would seem to be economical for the dairy operator, thereis a risk that infectious pathogens may be transmitted through the milkor shed directly from the cow's mammary gland. Other pathogens can bedeposited in milk from manure or dirt, or can result from proliferationin milk that is not chilled or stored properly.

To reduce this risk, it is preferred that milk or colostrum bepasteurized before feeding to calves. Pasteurization in known processesincludes heating milk to a target temperature to kill a target microbeand maintaining that temperature for a period of time. The pasteurizedmilk ordinance defines two different methods for pasteurization: 1)batch pasteurization at 145° F. for 30 minutes (low-temperature,long-time or LTLT), or 2) high-temperature, short-time pasteurization(HTST) at 161° F. for 15 seconds (usually using a continuous flowprocess). Heating and maintaining the heat above a target temperatureresults in a log reduction in concentration of viable bacteria. However,some heat-tolerant bacteria may survive the process. Further, in a poorquality milk with very high concentrations of bacteria, some pathogenicbacteria may survive the pasteurization process.

Pasteurization is desirable and sometimes necessary to kill bacteria,such as E. coli, B. Cereus, and salmonella that are harmful to calves.Heat pasteurization to 145° F. is successful at killing nearly 100% ofthese bacteria if the milk is maintained above 145° F. for at leastthirty minutes. One study suggests that a lower temperature of 120° F.can be used, but that temperature must be maintained for at least sixtyminutes.

Once pasteurized, milk may be bottled, chilled, stored, and thenreheated to a feeding temperature of between 100° F. to 110° F. It maynot be necessary to store pasteurized milk because it is more readilyavailable and can be fed directly to calves after it is heat pasteurizedand cooled to feeding temperature.

Also, colostrum is fed to newborn calves within two hours of birth andagain within twelve hours of birth. Colostrum is collected from cowsshortly after calving, and includes relatively high concentrations ofcarbohydrates, protein, and antibodies. Colostrum also contains highconcentrations of immunoglobulins, such as IgG, and growth factors.Pasteurizing colostrum can result in congealing and loss ofimmunoglobulins. About 25% to 30% of IgG concentrations in colostrum aredestroyed in heat pasteurization of colostrum and milk. Thus, heatpasteurization is beneficial overall, but has detrimental affects onmilk and colostrum. Colostrum is usually chilled, bottled, and storedprior to re-heating and feeding.

Ultraviolet pasteurizers can also be used to treat milk. U.S. Pat. No.6,916,452, to Rix et al. discloses that milk can be sterilized in adairy using one or more UV sterilizer units while maintaining milktemperature above 82.4° F. (28° C.) before it is transferred to achiller and a bulk milk storage vat. Such a pasteurizer is conceptuallywell-founded, but is not able to be used on its own in a dairy facilitybecause it lacks critical features necessary to prepare the milk andcolostrum for distribution and feeding to calves.

An improved pasteurization system is needed that successfully killsharmful bacteria, but destroys little or no immunoglobulins for optimumcalf health.

SUMMARY OF THE INVENTION

The present invention is directed to a system and method forpasteurizing milk and/or colostrum for feeding to calves. The term“milk” as used herein should be understood to include milk, colostrum,other calf feed, and any related supplements. “Calves” as used hereinincludes any dairy animal such as cows, goats, and sheep.

The system includes a vat or vat for storing milk or colostrum, acirculation pump and piping system, a heat exchanger for adjustingand/or maintaining milk temperature, and an ultraviolet lightpasteurizing unit (“UV reactor”). A controller activates the pump tocirculate milk to a heat exchanger to raise milk temperature to between85° F. and 120° F. and then circulates the warmed milk through the UVreactor at an appropriate rate and frequency to kill harmful bacteria.The milk can then be chilled and stored or fed directly to calves. Byraising the milk temperature to only the range of 85° F. to 120° F.,there is much less destruction of immunoglobulins and the milk is stillsafely pasteurized by the UV light from the UV reactor.

Unlike batch pasteurizers, UV reactors do not rely on the temperature ofthe milk to kill bacteria. Instead, the UV light alone in the range of200 to 280 nanometers, UVC range (germicidal range), kills the bacteria.Nonetheless, milk temperature is important because cold milk is churnedby the pump and piping system, and butter flakes can form that are lesslikely to be adequately treated by the UV light. Raising milktemperature to 85° F. or higher is sufficient to melt or reduce the sizeof butter flakes that form so that the milk is adequately treated by theUV reactors. Preferably, the milk temperature is raised to above 95° F.,and more preferably to above 100° F. to ensure proper milk viscositywith minimal butter concentrations. On the other hand, heating milk totoo high of a temperature can destroy beneficial immunoglobulins. Anupper end of the temperature range to minimize destruction of theimmunoglobulins is 120° F., and preferably 115° F., and more preferably110° F.

A temperature range of about 85° F. to about 120° F. includes a feedingtemperature range of between about 100° F. and about 110° F. If the milkis to be fed directly to calves, then heating to the feeding temperaturerange of between about 100° F. to 110° F. for pasteurizing isappropriate.

If the milk is to be chilled and stored after pasteurization, a milktemperature in the lower end of the range of 85° F. to 120° F. willproduce adequate results with the present invention and reduce energyrequirements. It is noted that treated waste milk may need to betransported to the calves where they are kept in the dairy facility. Inthis situation, heating the milk to above the feeding temperature rangecan compensate for milk cooling as it is being transported. Heat loss isa function of ambient conditions, the time between pasteurization andfeeding, and other factors. Thus, using the present invention, milktemperature can be adjusted to compensate for these and other factors inany particular dairy situation.

Apparatus in accordance with the present invention can include one ormore UV milk pasteurizer reactors, flow controllers, temperaturecontrollers, and devices for setting and adjusting optimal milktemperature for milk leaving the apparatus to accommodate calf needs,temperature losses for time, distance and methods for transporting themilk to calves.

UV milk pasteurizers for use in the present invention can be those ofthe type disclosed in Rix et al., U.S. Pat. No. 6,916,452 (incorporatedherein by reference). A number of such pasteurizers can be used inseries to reduce the number of times milk is circulated through the UVreactors.

Preferably, the controller of present invention monitors UV reactorcomponents and adjusts treatment time to accommodate defective UV bulbs,ballasts, or related components.

Flow controllers for use in the present invention include pumps andmeters that pump milk through the UV reactor at a rate that ensuresoptimal sterilization of milk and/or colostrum and prevents stagnationin the UV reactor related piping, connections, and control systems.Preferably, the flow rate is about 17 gallons per minute, but other flowrates may be used as the number, size, and efficiency of UV reactorschanges.

Temperature controllers for use in the present invention can includesensors and heat exchangers to warm or cool the milk to an optimumtemperature range for cooling and storage, for calves to be fed withmilk directly from the pasteurizing apparatus or for accommodatingtemperature losses in milk lines, containers or other equipment disposedbetween the apparatus and the calves. The pasteurizing temperature canbe adjusted accordingly because in the present invention, milktemperature does not contribute to pasteurizing.

The present invention also can include a stand pipe with milk volumedetector for determining the amount of milk in the vat, and calculatingand controlling treatment time based on milk quantity. For example, a100 gallon vat can be filled or partially filled with 100 gallons or 5gallons of milk, and the present invention will automatically set anapproximate treatment time.

Apparatus of the present invention can also include a mobile storage vatfor transporting pasteurized milk to the calves at remote locations. Themobile vat can be insulated and include a spray ball or device forcleaning the mobile vat. A mobile platform may simply transport the vatin which the milk was stored during pasteurization.

Other features and benefits of the invention will be apparent from thedetailed description and drawings of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a milk treatment system in accordance withthe present invention;

FIG. 2 is a perspective view of a milk treatment system in accordancewith the present invention;

FIG. 3 is a perspective view of the milk treatment system of FIG. 2 withits controller removed;

FIG. 4 is a front view of the milk treatment system of FIG. 2 andincluding a storage vat for milk in accordance with the presentinvention;

FIG. 5 is a schematic view of the milk treatment system with a mobileplatform for transporting the storage vat, in accordance with thepresent invention;

FIG. 6 is a front and partial cross-sectional view of a storage vat andstand pipe in accordance with the present invention; and

FIG. 7 is a schematic view of the milk treatment system illustrated inFIG. 1, but with a cross-sectional view of the UV reactor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description of the invention, the same referencenumeral will be used to identify the same or similar elements in theeach of the figures. FIGS. 1 through 5, and 7 illustrate a waste milktreatment system 20 in accordance with the present invention, including:a controller 22; a milk pump 24; an inlet conduit 26; an outlet conduit28; a pump inlet conduit 29; an ultraviolet milk treatment device 30(referred to herein as “UV reactor”); and an outlet conduit 32. Astorage vat 34 and a mobile platform 36 (FIG. 5) are used in connectionwith the milk treatment system 20.

Generally, the depicted milk treatment system 20 uses the milk pump 24to pump milk through the inlet conduit 26, and into the UV reactor 30.While being treated in the UV reactor 30, the milk is heated or cooledin a heat exchanger to be in a temperature range that minimizes thegrowth of bacteria without destroying the immunoglobulins that areimportant for calf health. The treated milk moves through the outletconduit 28 to be temperature adjusted and stored in the storage vat 34.The milk storage vat 34 may be supported on the mobile platform 36 fortransporting the milk to calves before the treated milk falls out of apredetermined temperature range. The mobile platform 36 may also includea milk distribution pump 39 to pump milk through a feed tube 41 tocalves.

More specifically, the controller 22 activates the pump 24 to circulatemilk to the UV reactor 30 which is preferably surrounded by a heatexchanger 38 to raise milk temperature to between 85° F. and 120° F. andthen circulates the warmed milk through the UV reactor 30 at anappropriate rate and frequency to kill harmful bacteria. The milk canthen be chilled and stored or fed directly to calves. By raising themilk temperature to only the range of 85° F. to 120° F., there is muchless destruction of immunoglobulins and the milk is still safelypasteurized by the UV light from the UV reactor 30.

Unlike batch pasteurizers, UV reactors do not rely on the temperature ofthe milk to kill bacteria. Instead, the UV light alone in the range of200 to 280 nanometers, UVC range (germicidal range), kills the bacteria.Nonetheless, milk temperature is important because cold milk is churnedby the pump and piping system and butter flakes can form that are lesslikely to be adequately treated by the UV light. Raising milktemperature to 85° F. or higher is sufficient to melt or reduce the sizeof butter flakes that form so that the milk is adequately treated by theUV reactors. Preferably, the milk temperature is raised to above 95° F.,and more preferably to above 100° F. On the other hand, heating the milkto too high of a temperature can destroy beneficial immunoglobulins. Anupper end of the temperature range to minimize destruction of theimmunoglobulins is 120° F.

A temperature range of about 85° F. to about 120° F. includes a feedingtemperature range of between about 100° F. and about 110° F. If the milkis to be fed directly to calves, then heating to the feeding temperaturerange of between about 100° F. to 110° F. for pasteurizing isappropriate.

If the milk is to be chilled and stored after pasteurization, a milktemperature in the lower end of the range of 85° F. to 120° F. willproduce adequate results in the present invention. It is noted thattreated waste milk may need to be transported to the calves where theyare kept in the dairy facility. In this situation, heating the milk toabove the feeding temperature range can compensate for milk cooling asit is being transported. Heat loss is a function of ambient conditions,the time between pasteurization and feeding, and other factors. Thus,using the present invention, milk temperature can be adjusted tocompensate for these and other factors in any particular dairysituation.

A preferred heat exchanger 38 for use with the present invention isdisposed around the UV reactor 30. The heat exchanger 38 is depicted inFIG. 7 and includes an inlet 62, a water jacket 64, and an outlet 66.The water jacket 64 surrounds and is substantially coaxial with the UVreactor 30 to define an annular space through which water, air or otherheat exchanger fluid can flow to adjust the temperature of the UVreactor 30 and the milk being pasteurized therein. Preferably, the waterjacket 64 is made of stainless steel, but other materials can be used.The inlet 62 is in communication with a source of water or other fluid,and the fluid source can be a hot water heater, for example. Preferably,the hot water heater is a dedicated unit for the heat exchanger 38, in aclosed loop configuration with the heat exchanger 38.

Other types of heat exchangers can be used with the present invention,and be positioned at any point in the milk flow path.

A temperature sensor 44 is used to determine milk temperature throughoutthe pasteurizing process. Preferably, the temperature sensor 44 is aPrecision Fahrenheit Temperature Sensor Model LM34, available fromNational Semiconductor. If the pasteurization process has been completedand the desired milk temperature has not been reached, milk willcontinue to be circulated until the desired temperature is reached.

Further, the controller 22 is preferably in communication with a milkquantity sensor 43, which is preferably an integrated silicon pressuresensor (MPX5010GP, Case 867b-04) available from Freescale Semiconductor(www.freescale.com) that uses a long stand tube 42 that traps air whenthe liquid level of the vat 34 increases. As the milk level in the vat34 rises, pressure in the long stand tube 42 increases. The milkquantity sensor 43 generates a voltage readout signal that iscommunicated to the controller 22 to automatically determine run timefor any batch size of milk.

Preferably, the controller 22 is set initially by a skilled installer ortechnician. Adjustments can be made by any dairy operator at an operatorinterface 45 to adjust temperature, flow rates, treatment time or anyother condition in the pasteurizing process.

The controller 22 also provides a display 42 indicating how long it hasbeen since the pasteurizing process has been completed and the milk'scurrent temperature so that re-circulation through the heat exchanger 38can bring milk temperature back within a desired range. The display 42can provide a dairy operator with any relevant information, includingoperating times, flow rates, milk temperature, component failure,maintenance requirements, and so on.

Finally, after pasteurized milk has been distributed to calves or themobile platform 36, the milk treatment system 20 can be coupled to awash system (not illustrated) for automatic cleaning and preparation forthe next pasteurizing cycle.

The milk treatment system 20 can include one or more UV milk pasteurizerreactors 30. Three UV reactors 30 are used in the illustratedembodiment. UV milk pasteurizers for use in the present invention can bethose of the type disclosed in Rix et al., U.S. Pat. No. 6,916,452(incorporated herein by reference). The UV reactors 30 as depicted inFIG. 7 include an inlet 50, an outlet 60, a quartz tube 52, a UV lightbulb 56 disposed inside the quartz tube 52 to prevent milk fromcontacting the light bulb 56. Other types of tubes can be used toprotect the light bulb 56 from being damaged by milk. Surrounding thequartz tube 52 is an outer tube 58 (preferably made of stainless steel)that defines with the quartz tube 52, an annular milk flow channel. Theheat exchanger 38 surrounds the outer tube 58. Milk flows through theinlet 50, the annular flow channel 58 where it is pasteurized by UVlight, and out the outlet 60.

The UV light bulb 56 is preferably a GIA972T5LCA/2S07/PT-18″/4W/N/CB-061(UV Pure) available from First Light Technologies, Inc., P.O. Box 191,212 Ideal Way, Poultney, Vt. 05764. Ballasts for use in the UV reactor30 preferably are Electronic Ballasts, EVG 100 . . . 200W/230V AC,available from ZED—Ziegler Electronic Devices GmbH. The quartz tube 52is about one inch in outside diameter and the inside diameter of theouter tube 58 is about 1.37 inches. Further, the outside diameter of theouter tube 58 is about 1.50 inches in diameter and the inside diameterof the water jacket 64 is about 2.37 inches, but other dimensions of thewater jacket 64 are possible.

Other combinations of bulbs and ballasts are possible, and it isdesirable that the combination be UL rated. The UV reactors 30 can beused in series or parallel to reduce the number of times milk iscirculated through the UV reactors. Preferably, the controller 22 of thepresent invention is in monitoring communication to monitor UV reactor30 components and adjust treatment time to accommodate defective UVlight bulbs 56, ballasts or related components. One way to monitor suchcomponents is to monitor electrical current flow through a light bulb,for example. If the bulb is not working no current will be flowingthrough the bulb.

The pump 24 pumps milk through the UV reactor 30 at a rate that ensuresoptimal sterilization of milk and/or colostrum and prevents stagnationin the UV reactor 30 related piping, connections, and control systems.Preferably, the flow rate is about 17 gallons per minute, but other flowrates may be used as other system components are changed in size ortype.

Preferably, the controller 22 is programmed to operate the milk pump 24at about seventeen gallons per minute flow rate. Using one UV reactor 30alone, this flow rate will result in pasteurized milk after about 40“passes” through the UV reactor 30. Using two UV reactors 30 in serieswill require about 20 passes, and using three UV reactors in series willrequire about 13.4 passes through the reactors 30.

For fifty gallons of waste milk at 2.9 minutes per pass, the UVpasteurizing process will take about 59 minutes. This is an improvementover batch pasteurizing heating, treatment, and cooling times. Further,the present invention saves time and energy primarily because the milkdoes not require heating to such high temperatures. Tests have shown 30%to 70% time savings for the present invention over the batchpasteurizing process.

Further, the present invention promotes efficiencies in dairies becausea milk vat 34 can be filled hours before milk is needed, and thepasteurizing process can be initiated automatically by the controller 22at an appropriate time to warm, pump, pasteurize and store the milk on amobile platform 36 for transport to calves. This function is preferablyset by a pasteurization start timer accessible at the operator interface45.

As depicted in FIG. 6, the present invention also can include a standpipe 42 with milk volume detector 38 for determining the amount of milkin the vat 34. The controller 22 calculates and controls treatment timebased on the milk quantity in the vat 34. For example, a 100 gallon vat34 can be filled or partially filled with 100 gallons or 5 gallons ofmilk, and the present invention will automatically set the approximatetreatment time.

Apparatus of the present invention can also include a mobile platform 36(FIG. 5) or storage vat 34 for transporting the milk from thepasteurizer to the calves at remote locations. The mobile vat 36 can beinsulated and include a spray ball or device for cleaning the mobile vat36. A mobile platform 36 may simply be a frame and wheels to transportthe vat 34 in which the milk was stored during pasteurization.

Comparisons between the present invention and the prior art batchpasteurizers illustrate the efficacy of the present invention for usewith waste milk and colostrum.

EXAMPLE A

In this example A, the standard batch pasteurizer is more effective thanthe UV pasteurizer for all the organisms tested in killing harmfulbacteria, but when milk is used, the invention is effective for allthree organisms tested (99.98% for E. coli, 100% for B. cereus and99.992% for Salmonella). However, when colostrum is used the inventionis certainly less effective for all three to the point where it may notbe effective enough. More research may be needed to determine themaximum effectiveness, in terms of increasing treatment time, foreffective bactericidal action on microorganisms when present incolostrum.

Further, single Radial immunodiffusion assays were also run for thesesamples for bovine IgG. The batch pasteurizer samples displayed asignificant reduction in IgG (around 43%) whereas the UV samples had noreduction in IgG at all. Thus, the present invention as shown in ExampleA results in healthier waste milk, but possibly not healthier colostrum.

CFU/ml % Survival % Kill Batch Pasteurizer time- substrate E. coli ATCC# 25922 Pre heat-milk^(a) 3.93 × 10⁶ — — Time 0 minutes-milk^(b) 4.60 ×10³ 0.007%    99.88%   Time 10 minutes-milk 0 0% 100% Time 20minutes-milk 0 0% 100% Time 30 minutes-milk 0 0% 100%Pre-heat-colostrum^(a) 2.31 × 10⁶ — — Time 0 minutes-colostrum^(b) 0 0%100% Time 10 minutes-colostrum 0 0% 100% Time 20 minutes-colostrum 0 0%100% Time 30 minutes-colostrum 0 0% 100% UV Pasteurizer time- substrateE. coli ATCC # 25922 Time 0 minutes-milk 4.41 × 10⁶ — — Time 5minutes-milk 1.30 × 10⁵ 2.95%   97.1%  Time 10 minutes-milk 3.73 × 10³0.085%    99.92%   Time 15 minutes-milk 9.30 × 10² 0.021%    99.98%  Time 0 minutes-colostrum 8.68 × 10⁶ — — Time 5 minutes-colostrum 6.65 ×10⁶ 76.6%   23.4%  Time 10 minutes-colostrum 2.60 × 10⁶ 30.0%   70.0% Time 15 minutes-colostrum 1.88 × 10⁶ 21.7%   78.3%  Batch Pasteurizertime- substrate Bacillus cereus ATCC # 4342 Pre heat-milk^(a) 1.08 × 10⁵— — Time 0 minutes-milk^(b)  17.5 0% 100% Time 10 minutes-milk 0 0% 100%Time 20 minutes-milk   0.5 0% 100% Time 30 minutes-milk^(a)  22.5 0%100% Pre-heat-colostrum^(a) 1.10 × 10⁵ — — Time 0 minutes-colostrum^(b) 12.5 0% 100% Time 10 minutes-colostrum   2.5 0% 100% Time 20minutes-colostrum   2.5 0% 100% Time 30 minutes-colostrum   2.5 0% 100%UV Pasteurizer time-substrate Bacillus cereus ATCC # 4342 Time 0minutes-milk 1.61 × 10⁵ — — Time 5 minutes-milk 1.11 × 10⁴ 6.89%  93.1%  Time 10 minutes-milk 1.80 × 10² 0.1118%    99.89%   Time 15minutes-milk  12.5 0% 100% Time 0 minutes-colostrum 1.88 × 10⁵ — — Time5 minutes-colostrum 5.83 × 10⁴ 31.0%   70.0%  Time 10 minutes-colostrum2.48 × 10⁴ 13.2%   86.8%  Time 15 minutes-colostrum 1.47 × 10⁴ 7.8%  92.2%  Batch Pasteurizer time- substrate Salmonella cholerasuis ATCC #6539 Pre heat-milk^(a) 3.08 × 10⁶ — — Time 0 minutes-milk^(b) 1.50 × 10²0.0049%    99.995%   Time 10 minutes-milk 5 0% 100% Time 20 minutes-milk0 0% 100% Time 30 minutes-milk 0 0% 100% Pre-heat-colostrum^(a) 7.27 ×10⁵ — — Time 0 minutes-colostrum^(b) 0 0% 100% Time 10 minutes-colostrum0 0% 100% Time 20 minutes-colostrum 0 0% 100% Time 30 minutes-colostrum0 0% 100% UV Pasteurizer time-substrate Salmonella cholerasuis ATCC #6539 Time 0 minutes-milk 3.22 × 10⁶ — — Time 5 minutes-milk 4.52 × 10⁴1.40%   98.6%  Time 10 minutes-milk 8.25 × 10² 0.026%    99.97%   Time15 minutes-milk 2.68 × 10² 0.0083%    99.992%   Time 0 minutes-colostrum2.88 × 10⁶ — — Time 5 minutes-colostrum 6.68 × 10⁵ 23.2%   76.8%  Time10 minutes-colostrum 1.39 × 10⁵ 4.83%   95.2%  Time 15 minutes-colostrum8.41 × 10⁴ 2.92%   97.1%  ^(a)Substrate (milk or colostrum) before anyheating. ^(b)Substrate (milk or colostrum) right after getting up to thepasteurization temperature (time = 0). This takes about one-half anhour.

EXAMPLE B

For this example, the UV Pasteurizer trial for the milk was repeated,with the addition of another time at 22 minutes exposure of the milk toUV light. These results are very similar to Example A with asatisfactory level of kill after 15 minutes exposure for 10 gallons ofmilk with all three bacteria tested.

The second part of the study utilized colostrum which Example A had anineffective level of kill after 15 minutes for the organisms tested.Example B utilized exposure levels of 30 and 45 minutes. These resultsindicated better efficacy in two of the three organisms at 15 minutesversus Example A. Example A shows the efficacy at 15 minutes to bemarginal for two organisms and unacceptable for the third (Bacillus). Atboth 30 and 45 minutes exposure, however, the efficacy of thepasteurizer of the present invention for all three organisms wasadequate to very good.

Further, Single Radial immunodiffusion assays were also run for thesesamples for bovine IgG. The results indicated no reduction inimmunoglobulin (IgG) after 15 minutes and a relatively minimal reductionin immunoglobulin (IgG) after 30 and 45 minutes. Thus, the presentinvention as reflected in Example B results in healthier milk andcolostrum than the prior art batch pasteurizer.

CFU/ml % Survival % Kill UV Pasteurizer time-substrate E. coli ATCC #25922 Time 0 minutes-milk 9.55 × 10⁶ — — Time 5 minutes-milk 1.81 × 10⁵ 1.90% 98.1% Time 10 minutes-milk 1.34 × 10³ 0.014% 99.986%  Time 15minutes-milk 4.53 × 10² 0.005% 99.995%  Time 22 minutes-milk 6.50 × 10¹0.0007%  99.9993%   Time 0 minutes-colostrum 1.47 × 10⁷ — Time 15minutes-colostrum 1.28 × 10⁵  0.87% 99.1% Time 30 minutes-colostrum 7.03× 10³ 0.048% 99.95%  Time 45 minutes-colostrum 2.92 × 10² 0.002%99.998%  UV Pasteurizer time-substrate Bacillus cereus ATCC # 4342 Time0 minutes-milk 5.07 × 10³ — — Time 5 minutes-milk 2.26 × 10³ 44.58%55.4% Time 10 minutes-milk 2.80 × 10¹  0.56% 99.4% Time 15 minutes-milk3.3 0.065% 99.93%  Time 22 minutes-milk 0      0%  100% Time 0minutes-colostrum 1.43 × 10⁴ — — Time 15 minutes-colostrum 5.18 × 10³ 36.0% 63.8% Time 30 minutes-colostrum 3.67 × 10²  2.57% 97.4% Time 45minutes-colostrum 8.3 0.058% 99.94%  UV Pasteurizer time-substrateSalmonella cholerasuis ATCC # 6539 Time 0 minutes-milk 4.66 × 10³ — —Time 5 minutes-milk 6.30 × 10¹  1.35% 98.6% Time 10 minutes-milk 0     0%  100% Time 15 minutes-milk 2.83 × 10¹  0.61% 99.3% Time 22minutes-milk 6.7  0.14% 99.86%  Time 0 minutes-colostrum 3.72 × 10⁶ — —Time 15 minutes-colostrum 2.68 × 10⁴  0.72% 99.28%  Time 30minutes-colostrum 5.73 × 10² 0.0154%  99.98%  Time 45 minutes-colostrum 3.0 × 10¹ 0.0008%  99.9992%  

EXAMPLE C

This example utilized colostrum at the same exposure levels of 15, 30and 45 minutes as Example B. These results indicated that the UVPasteurizer of the present invention overall is still effective at 30and 45 minutes, especially the latter time. The only possible exceptionis possibly the Bacillus where only the 45 minute exposure time showedsolid results. The results generally showed less percent kill then theprevious test at the same exposure times, but the Time 0 concentrationswere also higher, which probably accounts for this reduction in kill. Inreal field use, the concentration of these pathogens is very unlikely tobe anywhere near what is being tested in this example. It can thereforebe concluded that the kill rates are satisfactory at both 30 and 45minutes.

Further, Single Radial immunodiffusion assays were also run for thesesamples for bovine IgG. The results indicated minimal or no reduction inimmunoglobulin (IgG) after 15, 30 and 45 minutes. This is therefore, adistinct improvement over batch pasteurizing.

CFU/ml % Survival % Kill UV Pasteurizer time-substrate E. coli ATCC #25922 Time 0 minutes-colostrum 3.40 × 10⁷ — — Time 15 minutes-colostrum3.26 × 10⁶ 9.59% 90.4% Time 30 minutes-colostrum 1.26 × 10⁵ 0.37% 99.6%Time 45 minutes-colostrum 3.68 × 10³ 0.011%  99.989%  UV Pasteurizertime-substrate Bacillus cereus ATCC # 4342 Time 0 minutes-colostrum 2.16× 10⁴ — — Time 15 minutes-colostrum 1.22 × 10⁴ 56.5% 43.5% Time 30minutes-colostrum 1.14 × 10³ 5.28% 94.7% Time 45 minutes-colostrum 8.50× 10¹ 0.39% 99.6% UV Pasteurizer time-substrate Salmonella cholerasuisATCC # 6539 Time 0 minutes-colostrum 1.16 × 10⁷ — — Time 15minutes-colostrum 6.33 × 10⁵ 5.46% 94.5% Time 30 minutes-colostrum 1.56× 10⁴ 0.13% 99.87%  Time 45 minutes-colostrum 6.75 × 10² 0.0058% 99.994%  ^(a)Colony-forming units per ml.

The above examples illustrate the effectiveness of the present inventionin killing three types of pathogens while preserving essentially all ofthe immunoglobulins in milk and colostrum.

The previous detailed description of the preferred embodiments of theinvention are presented for clearness of understanding, and are notintended to limit the scope of the following claims. Further, the term“milk” as used in the claims is intended to be broad enough to includemilk, waste milk, non-saleable milk, colostrum or any other calf feedsupplement that would benefit from pasteurizing prior to feeding tocalves.

The invention claimed is:
 1. A milk treatment system comprising: anultraviolet milk treatment device having an inlet and an outlet; astorage vat in fluid communication with the ultraviolet milkpasteurizing treatment device; a pump in fluid communication with thestorage vat; a milk heat exchanger in which the milk treatment device isat least partially disposed; and a controller in communication with thepump and heat exchanger.
 2. The milk treatment system of claim 1,wherein the ultraviolet milk treatment device comprises: a plurality ofultraviolet milk treatment reactors.
 3. The milk treatment system ofclaim 1, and further comprising: a mobile platform supporting thestorage vat.
 4. The milk treatment system of claim 1, and furthercomprising: a mobile platform supporting the milk vat; and thecontroller comprises: a milk temperature adjuster.
 5. The milk treatmentsystem of claim 1, wherein the controller is in monitoring communicationwith the ultraviolet milk treatment device.
 6. The milk treatment systemof claim 1, and further comprising: a milk quantity sensor in fluidcommunication with the storage vat and the controller.
 7. The milktreatment system of claim 1, wherein the controller includes an operatorinterface for adjusting the controller.
 8. The milk treatment system ofclaim 1, wherein the controller comprises: a pasteurization start timer.9. A milk treatment system comprising: an ultraviolet milk treatmentdevice having an inlet and an outlet; a storage vat in fluidcommunication with the ultraviolet milk treatment device; a pump influid communication with the storage vat; a milk heat exchanger, whereinthe milk heat exchanger comprises a water jacket surrounding at least aportion of the ultraviolet milk treatment device; and a controller incommunication with the pump and heat exchanger.
 10. A milk treatmentsystem comprising: an ultraviolet milk treatment device having an inletand an outlet; a storage vat in fluid communication with the ultravioletmilk treatment device; a pump in fluid communication with the storagevat; a milk heat exchanger; and a controller in communication with thepump and heat exchanger, wherein the controller adjusts the milk heatexchanger to a milk temperature range of about 85° F. and not to exceedabout 120° F.
 11. A milk treatment system comprising: an ultravioletmilk treatment device having an inlet and an outlet; a storage vat influid communication with the ultraviolet milk treatment device; a pumpin fluid communication with the storage vat; a milk heat exchanger; anda controller in communication with the pump and the milk heat exchangerto maintain milk in the ultraviolet milk treatment device for a milkexposure time of between about 15 minutes and about 60 minutes.
 12. Themilk treatment system of claim 11, wherein the milk exposure time isbetween about 30 minutes and about 45 minutes.